"It's a common belief that massage is better, but it isn't better. Massage and exercise had the same benefits," said Lars Andersen, the lead author of the study and a professor at the National Research Center for the Working Environment in Copenhagen.

Earlier research has shown that massage can offer some relief from work out soreness.

To see how well light exercise compares, Andersen and his colleagues asked 20 women to do a shoulder exercise while hooked up to a resistance machine.

The women shrugged their shoulders while the machine applied resistance, which engaged the trapezius muscle between the neck and shoulders.

Two days later, the women came back to the lab with aching trapezius muscles. On average they rated their achiness as a five on a 10 point scale, up from 0.8 before they had done the shoulder work out.

Then the women received a 10-minute massage on one shoulder and did a 10-minute exercise on the other shoulder. Some women got the massage first, while others did the exercise first.

The exercise again involved shoulder shrugs; this time the women gripped an elastic tube held down by their foot to give some resistance. (Hygenic Corporation, which makes the tubing used in the study, supported the study.)

Andersen's group found that, compared to the shoulder that wasn't getting any attention, massage and exercise each helped diminish muscle soreness.

The effect peaked 10 minutes after each treatment, with women reporting a reduction in their pain of 0.8 points after the warm up exercise and 0.7 points after the massage.

"It's a moderate change," said Andersen, whose study appeared in the Journal of Strength and Conditioning Research.

He said he expects that athletes would notice a difference in having their soreness reduced by this amount.

"I think that for athletes...by reducing soreness then they're able to perform better, but we didn't measure this. But if you are sore your movements are very stiff and it's difficult to perform," he said.

Andersen said he'd like to see future studies track whether warming up the muscles to relieve soreness does indeed impact how well athletes perform.

The study suggests that "maybe (massage or exercise) has some benefit for individuals prior to an activity, even though the benefit may be short-lasting," said Jason Brumitt, of the School of Physical Therapy at Pacific University, who was not involved in the research.

It's not clear how massage or exercise would relieve soreness, but Brumitt said that it's thought that they help to clear out metabolic byproducts associated with tissue damage.

Andersen recommends that people try light exercise to ease their pain. The effect is moderate, and only offers temporary relief, but the benefit of using exercise, Andersen said, is that it doesn't require a trained therapist or travel time.

"If people go out and exercise and get sore they can find some relief in just warming up the muscles," he said.

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